Ziden

iTrader: (3)

I recently replaced my old radiator in my 99 TA M6 becaue it had a crack just below the radiator cap. I went to AutoZone and purchased a new radiator which was thicker and it had a extra hole on it that I blocked off. I double checked the part numbers with Autozone and it is the same part number listed as a LT1 Radiator. After some research on here I found that the LT1 is a higher capasity radiator so all was good I guess as long as I blocked off the extra radiator hole. I replaced the radiator and filled it with water and I have noticed I can hear the water boiling and going into the over flow. It was fine fo rabout 3 days until this morning when the low coolant light came on. I can only think the reason it came on is because I filled the radiator with tap water and it boils over into the resivour and it is not returning to the radiator? If I go 50/50 with Dextron and Distilled water, should that fix the problem? The car has never overheated and it does not overheat now.

taintedmeat

iTrader: (1)

The reservoir is supposed to have coolant in it as well. You probably just don't have enough in your system. Just keep topping off the radiator until it stays full.

Also yeah, I would run the mix. Don't wanna corrode that new lt1 radiator too quick or get it clogged with minerals.

Ziden

iTrader: (3)

Dosent the resivour just over spill on the ground when its full or does it return the coolant to the radiator?

taintedmeat

iTrader: (1)

It actually has a fill line. Once your cooling system is completely full, the res. is meant to be filled to the fill line as well.

Also, if your radiator isn't full, it won't suck anything back out of the res.

Ziden

iTrader: (3)

OK, I see what your saying. The resivour may have been empty and nothing was being returned to the radiator?

taintedmeat

iTrader: (1)

Right, and now that there's a big pocket in the radiator, it can't suck anything back.